Combined defibrillation and pacing electrode

A set of electrodes, each of said electrodes comprising:

• an insulating substrate,
• a conducting plate having a top surface, a bottom surface, and an electrical terminal for making a connection to an external source of electrical current, said conducting plate being positioned with said bottom surface on said substrate, and
• a layer of electrolytic gel comprising a concentration of an electrolyte that produces a combination series resistance of two of said electrodes, when measured with the electrodes configured in a series circuit with a 50 .OMEGA. resistance, and with the electrolytic gel layer of each electrode in contact with that of the other electrode, that is greater than 1 .OMEGA. when a 200 Joule defibrillation pulse is discharged into the series circuit, said layer of electrolytic gel covering the entire top surface of said conducting plate, the gel contacting said patient's skin when the electrode is positioned on the patient's skin to thereby prevent said conducting plate from contacting the skin,
• said set of electrodes comprising a front electrode to be positioned on the front of a patient's chest and a back electrode to be positioned on the back of a patient's chest, the conducting plate of the front electrode having an area of at least 8 square inches and the conducting plate of the back electrode having an area of at least 8 square inches.

A method of transcutaneously defibrillating a patient's heart, the method comprising the steps of:

• generating an electrical defibrillation pulse, and
• delivering said pulse to said patient through electrodes applied to said patient's thorax, the electrodes each comprising:
• an insulating substrate,
• a conducting plate having a top surface, a bottom surface, and an electrical terminal for making a connection to receive said electrical defibrillation pulse, said conducting plate being positioned with said bottom surface on said substrate, and
• a layer of electrolytic gel comprising a concentration of an electrolyte that produces a combination series resistance of two of said electrodes, when measured with the electrodes configured in a series circuit with a 50 .OMEGA. resistance, and with the electrolytic gel layer of each electrode in contact with that of the other electrode, that is greater than 1 .OMEGA. when a 200 Joule defibrillation pulse is discharged into the series circuit, said layer of electrolytic gel covering the entire top surface of said conducting plate, the gel contacting a patient's skin when the electrode is positioned on the patient's skin to thereby prevent said conducting plate from contacting the patient's skin.